#define _CRT_SECURE_NO_WARNINGS 1
class Solution {
public:
    int minInsertions(string s) {
        int n = s.size();
        vector<vector<int>> dp(n, vector<int>(n));
        for (int i = n - 1; i >= 0; i--)
        {
            for (int j = i; j < n; j++)
            {
                if (s[i] == s[j] && i + 1 >= j) dp[i][j] = 0;
                else if (s[i] == s[j]) dp[i][j] = dp[i + 1][j - 1];
                else dp[i][j] = min(dp[i + 1][j], dp[i][j - 1]) + 1;
            }
        }
        return dp[0][n - 1];
    }
};